1. Field of the Invention
The invention relates to a mechanical transmission mechanism, more particularly to a mechanical transmission mechanism with rolling means which generates less friction loss when compared to a conventional mechanical transmission mechanism with balls that serves as a transmission medium so as to perform a work effectively.
2. Description of the Related Art
Referring to FIG. 1, a conventional mechanical transmission mechanism with balls that serve as a transmission medium is shown to comprise an input member 32, an output member 31 and a transmission medium 34 for transmitting a mechanical input which is received from the input member 32 in order to enable the output member 31 to perform work. As illustrated, the output and input members 31, 32 are in the form of pistons which are respectively and slidably inserted into two ends of a guide channel 30 while a row of successive balls are packed in the guide channel 30 and serve as the transmission medium 34. A compression spring 310 is sleeved around the output member 31 to bias the latter to return to its initial position after work has been performed. The input member 32 is connected to one end of a crank 33 which is driven by a rotary machine (not shown). The crank member 33 swings upon receipt of a driving force from the rotary machine, and the applied force is received by the input member 32 and is transmitted to the output member 31 via the transmission medium 34 in order to perform work.
In order to provide a uniform and even transmission force, the balls are in sliding contact with the inner surface of the guide channel 30. Each of the balls moves without rotating and transmits the applied force to a succeeding ball. Movement of the balls along the guide channel 30 generates friction which impedes and decreases the effectiveness of the driving force upon reaching the output member 31.